HI guys!!!

Have a problem with 3d array memory allocation in next code:

//////////////////////////////////////////////////////////
class NeuronNet(T, const uint layersNum)
{
	T[]					_inputs;
	T[][layersNum - 2]	_hidden;
	T[]					_outputs;
	T[]					_target;

	//waights [col][row][dimension]
	T[][][layersNum - 1] _waightsArray;

	this(in uint[] nodesArr)
	{
		//values init
		_inputs = new T[nodesArr[0]];
		_outputs = new T[nodesArr[$-1]];

		for(uint j = 0; j < layersNum - 2; j++)
		{
			_hidden[][j] = new T[nodesArr[j + 1]];
		}
		//waights init
		for(uint i = 0; i < layersNum - 1; i++)
		{
			_waightsArray[][][i] = new T[][nodesArr[1+i]];
			for(uint ii = 0; ii < nodesArr[1+i]; ii++)
			{
				_waightsArray[][ii][i] = new T[nodesArr[i]];
			}
		}
	}
}
//////////////////////////////////////////////////////////

debuger shows array range boundary error in line
				_waightsArray[][ii][i] = new T[nodesArr[i]];

Help me please if any one knows

On 02/26/2015 12:01 PM, Andrey wrote:> HI guys!!!
>
> Have a problem with 3d array memory allocation in next code:
>
> //////////////////////////////////////////////////////////
> class NeuronNet(T, const uint layersNum)
> {
>      T[]                    _inputs;
>      T[][layersNum - 2]    _hidden;
>      T[]                    _outputs;
>      T[]                    _target;
>
>      //waights [col][row][dimension]
>      T[][][layersNum - 1] _waightsArray;

(Unrelated: That may be a typo if its actually "weights".)

>      this(in uint[] nodesArr)
>      {
>          //values init
>          _inputs = new T[nodesArr[0]];
>          _outputs = new T[nodesArr[$-1]];
>
>          for(uint j = 0; j < layersNum - 2; j++)

Better:

    foreach (j; 0 .. layersNum - 2)

>          {
>              _hidden[][j] = new T[nodesArr[j + 1]];

You have extra [] up there. This is equivalent:

             _hidden[j] = new T[nodesArr[j + 1]];

The reason is, _hidden[] means "the entire _hidden slice" anyway. So, the empty [] has no meaning at all.

>          }
>          //waights init
>          for(uint i = 0; i < layersNum - 1; i++)
>          {
>              _waightsArray[][][i] = new T[][nodesArr[1+i]];

Same there:

             _waightsArray[i] = new T[][nodesArr[1+i]];

>              for(uint ii = 0; ii < nodesArr[1+i]; ii++)
>              {
>                  _waightsArray[][ii][i] = new T[nodesArr[i]];

You want to set ii'th element of the i'th element, right? This is the right way to do it in D:

    _waightsArray[i][ii] = ...

Unlike C and C++, the array syntax is natural in D. In other words, it is not "inside out".

     T[] --> A slice of Ts
     T[][] --> A slice of T slices
     T[][][layersNum - 1] --> A number of those

So, _waightsArray[i] is one of the slices that you've just set in the previous for loop.

Ali

On Thursday, 26 February 2015 at 23:25:22 UTC, Ali Çehreli wrote:
> On 02/26/2015 12:01 PM, Andrey wrote:> HI guys!!!
> >
> > Have a problem with 3d array memory allocation in next code:
> >
> > //////////////////////////////////////////////////////////
> > class NeuronNet(T, const uint layersNum)
> > {
> >      T[]                    _inputs;
> >      T[][layersNum - 2]    _hidden;
> >      T[]                    _outputs;
> >      T[]                    _target;
> >
> >      //waights [col][row][dimension]
> >      T[][][layersNum - 1] _waightsArray;
>
> (Unrelated: That may be a typo if its actually "weights".)
>
> >      this(in uint[] nodesArr)
> >      {
> >          //values init
> >          _inputs = new T[nodesArr[0]];
> >          _outputs = new T[nodesArr[$-1]];
> >
> >          for(uint j = 0; j < layersNum - 2; j++)
>
> Better:
>
>     foreach (j; 0 .. layersNum - 2)
>
> >          {
> >              _hidden[][j] = new T[nodesArr[j + 1]];
>
> You have extra [] up there. This is equivalent:
>
>              _hidden[j] = new T[nodesArr[j + 1]];
>
> The reason is, _hidden[] means "the entire _hidden slice" anyway. So, the empty [] has no meaning at all.
>
> >          }
> >          //waights init
> >          for(uint i = 0; i < layersNum - 1; i++)
> >          {
> >              _waightsArray[][][i] = new T[][nodesArr[1+i]];
>
> Same there:
>
>              _waightsArray[i] = new T[][nodesArr[1+i]];
>
> >              for(uint ii = 0; ii < nodesArr[1+i]; ii++)
> >              {
> >                  _waightsArray[][ii][i] = new T[nodesArr[i]];
>
> You want to set ii'th element of the i'th element, right? This is the right way to do it in D:
>
>     _waightsArray[i][ii] = ...
>
> Unlike C and C++, the array syntax is natural in D. In other words, it is not "inside out".
>
>      T[] --> A slice of Ts
>      T[][] --> A slice of T slices
>      T[][][layersNum - 1] --> A number of those
>
> So, _waightsArray[i] is one of the slices that you've just set in the previous for loop.
>
> Ali

I very much appreciate. The author of D-book respond to me. THANKS VERY MUCH!!!!!